The present invention pertains to an improved tiller tube column or shaft unit for a bicycle, tricycle or even quadricycle vehicle of the type having a drive cable system embodying conventional unidirectional (one-way) clutches mounted on the drive wheel or wheels of the vehicle, more specifically, the invention deals with the means for steering, changing speeds, and for braking such a vehicle.
Vehicles of a similar type have been known in the past and have been described to some extent in certain U.S. patents including U.S. Pat. Nos. 1,620,926; 1,154,616; 3,986,725; 1,653,889; 3,285,618; 1,529,012; 3,884,501; 3,895,825; and in an article in the Oct. 6, 1980 issue of Design News, entitled "Push-Pedal Bike Folds for Carrying". Although no tiller tube is employed in this foldable bike dubbed the "Urban", the bike is powered by up-and-down motion applied to pedals which pull a cable over a V-groove roller clutch sleeve which turns the drive wheel. Such prior art bicycles or vehicles of this type all involve complex heavy structures and are otherwise impractical and unsatisfactory for today's bikers who demand improved constructions of lighter design and better characteristic features.
Other prior art bicycles are shown in the following U.S. Pat. Nos. 3,485,509; 616,021; 3,834,733; 293,366; 248,531; 449,498; 618,580; 3,760,905; 3,954,282; 3,913,945; 3,498,634; 2,232,120; 2,198,942; and 4,063,747.
Further U.S. Pat. Nos. 3,889,974; 3,831,978; 3,375,023; 3,984,129; 3,920,263; 293,366; 3,834,721; 4,119,326; 4,005,611; 3,759,543; 617,273; 3,834,733 and 4,026,571 disclose other bicycle and tricycle designs embodying certain common elements, such as cable drive systems, but none of these prior art patents are believed to have attracted interest in recent years due also in part to their probably high cost and complicated constructions. Additional "Mechanical Drives For Human Power" for use with bicycles and tricycles are disclosed in the March 1981 issue of Design Engineering, but these systems are basically variations and modifications of the conventional roller-chain drive which still represents the most common drive system for practically all human powered vehicles.